A prosthetic device, or prosthesis, is an artificial substitute for a part of the body such as a limb. Most prostheses have sockets to attach the prosthesis to the amputee's residual limb. One of the challenges of socket design is to maintain a tight fit between the prosthesis and the residual limb, particularly during unweighting of the limb, such as in the swing phase of gait.
Hydrostatic socket designs typically include a gel liner that is placed over the residual limb of the amputee to couple the residual limb to the prosthesis. The prosthesis may include a hard outer socket and a soft intermediate socket that is placed between the gel liner and the hard socket. A bottom or distal attachment device is connected to the liner and engages with the hard socket to secure the prosthesis to the user. The attachment device is commonly a pin, also known as a shuttle lock. Unfortunately, these devices may be difficult for users to properly align since the user may be unable to see the attachment device while trying to engage the attachment device with the rest of the prosthesis. Donning a prosthesis may also be frustrating for older adults and people with diabetes because they often lack upper body strength that is needed to align and secure the sockets to one another. Additionally, these attachment devices require the user to stand during donning so that gravity may be used to align and secure the prosthetic components.